HDU 3486 Interviewe

题目链接：http://acm.hdu.edu.cn/showproblem.php?pid=3486

 

题目写的清清楚楚，认真读就能 AC 了，讨论区那些人都是没认真读题，模棱两可按照自己的意愿在写，写错了怪谁呢？

 

#include <cstdio>
#include <cmath>
#include <cstring>
#include <algorithm>
using namespace std;

const int maxn = 2e5 + 10;
int N, K;
int a[maxn], maxx[maxn][20];

void RMQ(int num) {
    for(int i = 1; i <= N; i ++)
        maxx[i][0] = a[i];

    for(int j = 1; j < 23; j ++) {
        for(int i = 1; i <= num; i ++) {
            if(i + (1 << j) - 1<= num)
                maxx[i][j] = max(maxx[i][j - 1], maxx[i + (1 << (j - 1))][j - 1]);
        }
    }
}

int QueryMax(int l, int r) {
    int k = (int)(log(r - l + 1) / log(2.0));
    int ans = max(maxx[l][k], maxx[r - (1 << k) + 1][k]);
    return ans;
}

int step(int p) {
    int q = 0, cnt = 0;
    for(int i = 1; i <= N; i += p) {
        q += QueryMax(i, i + p - 1), cnt ++;
        if(q > K) break;
    }
    return cnt;
}

int main() {
    while(~scanf("%d%d", &N, &K)) {
        if(N == -1 && K == -1) break;
        memset(maxx, 0, sizeof(maxx));
        memset(a, 0, sizeof(a));

        for(int i = 1; i <= N; i ++) {
            scanf("%d", &a[i]);
        }

        RMQ(N);

        int people = N + 1;

        for(int i = 1; i <= N; i ++) {
            int st = 1, en = i;
            int sum = 0;
            int p = 0;
            while(en <= N && st <= N && sum <= K) {
                sum += QueryMax(st, en);
                st += i;
                en += i;
                p ++;
            }

            if(sum <= K) {
                continue;
            }

            if(p < people) {
                people = p;
            }
        }

        if(people == N + 1) people = -1;

        printf("%d\n", people);
    }

    return 0;
}